Top Ten Overworld Themes in Pokémon Sun and MoonOverworld counts as being the theme of specific locations, and not while battling or encountering certain characters.
The Top Ten
This theme sounds very happy, adventurous and nostalgic! It makes me feel like we're on an adventure. - AsianBlood
This theme is it. The final ascent up the highest mountain in Alola, the culmination of Alola...but where are the trainers? This theme by itself is amazing, but come on Game Freak! You ruined a perfect Victory Road! - AsianBlood
This theme sounds so decrepit and ominous... it makes you feel like you shouldn't be here, just as it should. - AsianBlood
I simply love how relaxing this theme sounds! It makes me think of a seafaring adventure on the ocean, in foggy and distant lands. - AsianBlood
I love the Night version too, but I'm giving Day the position on the list. It sounds completely foreign to Alola, and yet completely at home...the Japanese theme it radiates is simply amazing! - AsianBlood
I really like how Hau'oli City's theme matches its atmosphere perfectly. A pastoral version of city life, with citizens that are all too happy to help you out on your journey. - AsianBlood
This theme really fits the isolated, but gritty, circumstances you are forced to face in the Vast Poni Canyon. - AsianBlood
This is possibly my favourite Route 1 theme in Pokémon, because I love the beginner feel that this theme gives off. It sounds happy and cheerful! - AsianBlood
This theme sounds chipper and nostalgic, and matches all the routes on Akala Island, diverse as they are! - AsianBlood
A relaxing and peaceful theme that makes you feel like you're searching for something in a beautiful environment. It especially matches the Melemele Meadow. - AsianBlood
Its got a relaxing jazz feel. One of few themes done on piano.